Dissertations / Theses: 'Surface water and groundwater interaction'

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Oxtobee, Jaime Peter Allan. "Groundwater/surface water interaction in a fractured bedrock environment." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ63350.pdf.

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Aradas, Rodolfo D. "Groundwater and surface water interaction for integrated catchment planning." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/12810/.

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Integrated Catchment Management (ICM), defined as the design of intervention strategies encompassing and integrating the fields of hydrology, environmental, social and economic science, is vital in order to reach sustainable solutions on a catchment basis. Modelling lies at the core of the ICM process as it supports baseline studies and enables analysis of proposed intervention measures both for present day conditions and under future scenarios. Its core role in ICM leads to the need to develop modelling into a more comprehensive activity within which the design of a modelling approach, selection of tools and need for linkages can be thoughtfully matched to the requirements of ICM. Initial research revealed a gap in this area, leading to development of a Framework for Catchment Modelling Studies (FCMS) intended to create a staged and systematic approach that could be used as a template for development of modelling exercises that strike the right balance between ICM needs, project costs and the availability of human and technical resources. To demonstrate the utility of the FCMS and populate it with application guidance, practical techniques and examples, technical research was focused on analysis of groundwater-surface water interaction in the Rio Salado Basin. This flatland of 175,000km2, is located in the Buenos Aires Province of Argentina and features widespread groundwater-surface water interaction as the key driver of the flooding in vast areas of the basin. This flooding currently limits the potential for agricultural and livestock development of what is, economically, most important region of the country. Research revealed that use of uncoupled groundwater-surface water models was inadequate to simulate observed flooding in a test area of the Rio Salado Basin, and a new program - iSISMOD - was developed by coupling MODFLOW (McDonald and Harbaugh, 1988) with ISIS (HR Wallingford and Halcrow, 1995) to permit dynamic coupling of both systems and support improved flood probability mapping. The research concludes that adoption of an FCMS approach would provide scientists and engineers with a systematic basis from which to think through technical issues involved in the modelling cycle, and would facilitate improved decision making on key issues, such as when uncoupled models must be replaced by coupled models. This systematic approach is not only resource-effective, it is more importantly essential to support development of integrated catchment management plans that are sustainable.

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Jones, Cullen Brandon. "Groundwater-Surface Water Interactions near Mosier, Oregon." PDXScholar, 2016. https://pdxscholar.library.pdx.edu/open_access_etds/3414.

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The town of Mosier, Oregon, is located near the east, dry end of the Columbia River Gorge, and the local area is known for cherry orchards that rely heavily on groundwater for irrigation. The CRBG groundwater system in Mosier has experienced groundwater declines of up to 60 meters due to over-pumping and or commingling. Declining groundwater levels have led to concerns over the sustainability of the resource, as it is the principle water source for irrigation and domestic use. Despite numerous previous studies of groundwater flow in CRBG aquifers here and elsewhere in the Columbia River basin, an aspect that has received relatively little attention is the interaction between groundwater and surface waters at locations where interflow zones are intersected by the surface waters. The objective of my research is to investigate how CRBG interflow zone exposures in Mosier Creek may be controlling groundwater elevations in the area. The methods used include: (1) geochemical analysis of well cuttings and detailed geologic mapping along area streams to identify interflow zones of individual CRBG flows, (2) analysis of stream discharge data and groundwater elevation data to confirm exchange of groundwater and surface waters, and (3) collection and analyses of 31 water samples from area wells, streams, and springs, to determine if waters from individual CRBG aquifers can be hydrochemically identified and to further constrain understanding of surface and groundwater interactions. My study confirms that the general elevation of the Pomona Member and Basalt of Lolo interflow zone creek exposure is coincident with the elevation where a change in slope of the decline trend in 2004 is seen in Mosier area well hydrographs. Furthermore, the results of stream discharge data indicated a close connection between drawdown from groundwater pumping during irrigation season and groundwater- surface water interaction. At the time of drawdown in the upper-most CRBG aquifer (Pomona), the stream transitions from gaining to losing water into the groundwater system. Elemental chemistry data indicates the Frenchman Springs Sentinel Gap aquifer waters are the most evolved waters in this study. Stable isotopic data reinforced this determination as the Sentinel Gap waters are the lightest, or most negative, with regard to δD and δ18O. Sentinel Gap samples were more depleted than other aquifer samples by 4.38 to 6.89 0/100 for δD and 0.39 to 0.59 0/100 for δ18O. The results of the general chemistry and isotope data reveal a more evolved chemical signature in lower watershed groundwater versus a less evolved signature for waters from wells located higher up on the Columbia Hills anticline. This was interpreted to be the result of the major structural features in the area providing for a more regional pathway of recharge in lower watershed groundwaters, versus a more local source of recharge for upper watershed groundwaters. There was also a pronounced commingled signature in the elemental ratios of lower watershed aquifer waters. The suspected mechanism of recharge to lower watershed wells is through younger Cascadian deposits upslope from the local watershed. The findings of this study reveal the importance of a detailed understanding of CRBG stratigraphy and its relation to surface waters, especially for other areas within the Yakima Fold Belt or Oregon and Washington. Studies that do not consider the influence that individual CRBG flows can have on groundwater-surface water interactions, and the groundwater system as a whole, run the risk of improperly assessing the groundwater resource for a region.

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Starzyk, Cynthia Ann. "Simulating surface water - groundwater interaction in the Bertrand Creek Watershed, B.C." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42520.

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This research investigates the nature and controls of surface water–groundwater interaction at the watershed scale, and investigates how mechanisms which control this interaction during baseflow conditions might best be represented within an integrated surface-subsurface numerical model. The study site is the 46 km² Bertrand Creek Watershed, which is situated in a glaciated landscape in southern western British Columbia. A conceptual model of surface water–groundwater interaction along Bertrand Creek is developed based on a field data collection program conducted during the dry seasons of 2006 and 2007. The investigation relies on a suite of field techniques to characterize the nature of the interaction, including hydrologic measurements, stream water chemistry, and point-based measurements of streambed flux. These measurements are complemented by an assessment of topographic slope over the alluvial aquifer to infer the groundwater flow direction. Results indicate that topography adjacent to the stream is a principal control on water exchange between Bertrand Creek and the underlying aquifer. Topography influences the direction of groundwater flow adjacent to the stream and determines the persistence and magnitude of groundwater discharge along the channel. The conceptual model is used to develop an integrated numerical model of Bertrand Creek Watershed using HydroGeoSphere. HydroGeoSphere is a three-dimensional physics-based model that simulates overland flow, unsaturated flow, and groundwater flow in a fully integrated manner. The watershed model is calibrated using field data collected in 2007, including measured streamflows, groundwater contributions to streamflow, hydraulic heads, soil moisture contents, and change in surface water height in a pond. The calibrated watershed model is then evaluated against, and suitably represents, hydrologic data collected in 2006. Simulating baseflows and the seasonal hydrologic response requires that features controlling the spatial distribution of recharge, such as surficial soils and topography, are adequately characterized and represented within the model. Model results further demonstrate that evapotranspiration, particularly transpiration within the riparian zone, is a significant control of baseflows in Bertrand Creek. Finally, the calibrated model is used as a predictive tool to assess the impact of groundwater withdrawals on streamflow depletion.

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au, Tony J. Smith@csiro, and Anthony John Smith. "Periodic forcing of surface water-groundwater interaction : modelling in vertical section." Murdoch University, 1999. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090617.93320.

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Sinusoidal variations in recharge can induce cyclical flows in surface water and groundwater. In this thesis, such time-dependent flows are explored in a coupled lakeaquifer system. The modelling extends previous steady state results and introduces new flow-visualisation techniques. Local responses in a 2D vertical section are illustrated for lakes within a 1D regional groundwater mound. The theory employs complex variables to decouple the periodic groundwater flows into separate steady state and fluctuating components. The time dependent behaviour causes the lake-aquifer flow to change between flowthrough, recharge and discharge regimes. Corresponding fluctuations between inflow and outflow across the lakebed allow interchange of lake water with the aquifer (recycling and recapture). This also gives rise to sinuous flowpaths that can result in apparent dispersion; the number and size of waves, cusps and loops is characterised by a nondimensional waviness ratio. Streakline plots are introduced and provide an intuitive impression of the time-dependent groundwater motion. Such plots are enhanced by animation and illustrate the complex and potentially dispersive nature of the flows. Interplay between the steady state and fluctuating responses determines the type and strength of flow regime transition. Importantly, there is an inverse relationship between head and flow in the fluctuating response. This is characterised by a dimensionless response time; a function of the aquifer geometry, hydraulic properties and period of fluctuation. During fast response, the recharge propagates mainly as fluctuation in flow, with small phase lags; particle trajectories form elliptical paths in the visualised flows. With a slower aquifer response, variation in recharge is manifest mostly as fluctuation in water level; cyclical perturbations in the flows are small and flows are nearly in steady state. The position of a lake within the regional setting, size of the lake, and ratio of lake to aquifer recharge are important to the steady state response. Flow-through regimes occur throughout the regional setting, but dominate when the lake is lower in the system and groundwater flow is greater. Discharge and recharge regimes occur higher in the flow system, when the ratio of lake to aquifer recharge is large in magnitude.

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Smith, Anthony John. "Periodic forcing of surface water-groundwater interaction: modelling in vertical section." Smith, Anthony John (1999) Periodic forcing of surface water-groundwater interaction: modelling in vertical section. PhD thesis, Murdoch University, 1999. http://researchrepository.murdoch.edu.au/689/.

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Sinusoidal variations in recharge can induce cyclical flows in surface water and groundwater. In this thesis, such time-dependent flows are explored in a coupled lakeaquifer system. The modelling extends previous steady state results and introduces new flow-visualisation techniques. Local responses in a 2D vertical section are illustrated for lakes within a 1D regional groundwater mound. The theory employs complex variables to decouple the periodic groundwater flows into separate steady state and fluctuating components. The time dependent behaviour causes the lake-aquifer flow to change between flowthrough, recharge and discharge regimes. Corresponding fluctuations between inflow and outflow across the lakebed allow interchange of lake water with the aquifer (recycling and recapture). This also gives rise to sinuous flowpaths that can result in apparent dispersion; the number and size of waves, cusps and loops is characterised by a nondimensional waviness ratio. Streakline plots are introduced and provide an intuitive impression of the time-dependent groundwater motion. Such plots are enhanced by animation and illustrate the complex and potentially dispersive nature of the flows. Interplay between the steady state and fluctuating responses determines the type and strength of flow regime transition. Importantly, there is an inverse relationship between head and flow in the fluctuating response. This is characterised by a dimensionless response time; a function of the aquifer geometry, hydraulic properties and period of fluctuation. During fast response, the recharge propagates mainly as fluctuation in flow, with small phase lags; particle trajectories form elliptical paths in the visualised flows. With a slower aquifer response, variation in recharge is manifest mostly as fluctuation in water level; cyclical perturbations in the flows are small and flows are nearly in steady state. The position of a lake within the regional setting, size of the lake, and ratio of lake to aquifer recharge are important to the steady state response. Flow-through regimes occur throughout the regional setting, but dominate when the lake is lower in the system and groundwater flow is greater. Discharge and recharge regimes occur higher in the flow system, when the ratio of lake to aquifer recharge is large in magnitude.

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Stahl, Mason Odell. "Surface-water groundwater interaction and arsenic mobilization in south and southeast Asia." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/99609.

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Thesis: Ph. D. in Environmental Engineering, Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Contamination of groundwater with geogenic arsenic is widespread throughout much of South and Southeast Asia and poses a serious health risk to the millions of individuals who consume this water. It is widely agreed that the dominant mechanism of arsenic mobilization is reductive dissolution of arsenic-bearing iron-oxides coupled to the oxidation of organic carbon. However, it is unclear why dissolved arsenic concentrations have reached the high levels currently observed in aquifers throughout the region. In particular, the influence of surface water recharge on arsenic contamination remains unresolved. To address this issue we studied the hydrogeology and geochemistry of two arsenic contaminated sites: one site in Vietnam and another site in Bangladesh. Our field site in Vietnam is located adjacent to the Red River and has been impacted by intensive groundwater pumping for decades. The aquifer now receives net recharge from the river. We conducted a hydrogeologic and geochemical investigation to determine the influence of riverine recharge on groundwater arsenic concentrations. We determined that rates of arsenic mobilization in freshly deposited riverbed sediments are up to 1000 times those of inland aquifer sediments and measured arsenic concentrations in riverbed porewaters that exceeded the aquifer concentrations. We found the effect of riverine recharge is controlled by the geomorphic setting of the river-aquifer interface. Aquifers inland of freshly deposited river reaches are highly contaminated with dissolved arsenic, whereas aquifers inland of non-depositional river reaches host low arsenic groundwater. At our Bangladesh field site the aquifer has been impacted by the construction of man-made ponds, which provide 40% of aquifer recharge. To investigate the role of ponds on groundwater arsenic levels we constructed and instrumented a pond, installed a network of 100 wells, performed laboratory experiments, and collected sediment and water samples over three years. Our characterization of the pond physical hydrology and the pond and aquifer geochemistry reveals that arsenic mobilization within the aquifer is primarily driven by sedimentary organic matter. While ponds contribute substantial aquifer recharge our results suggest that high arsenic concentrations in Bangladesh are not driven by surface water recharge and likely emerged prior to anthropogenic perturbations to the hydrology.
by Mason Odell Stahl.
Ph. D. in Environmental Engineering

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Porter, Sandra. "Groundwater/surface water interaction in the Raisin River watershed, near Cornwall, Ontario." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/10133.

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A field study was conducted in 1994 and 1995 to understand the interaction of groundwater and surface water in the Raisin River watershed, near Cornwall, Ontario. The Raisin River lies within an agricultural region which relies heavily on groundwater use. The regional groundwater supply is predominantly from a limestone aquifer which underlies various surficial deposits (primarily glacial till). Groundwater movement appears to be in a southeasterly direction, towards the St. Lawrence River. Seepage meters, mini-piezometers, and a falling head permeameter were used to (i) measure the flux of groundwater into (positive seepage) or out (negative seepage) of the Raisin River, and (ii) measure the hydraulic conductivity of the Raisin River sediments. Measurements were made at thirteen sites within the watershed. To identify the source of groundwater and study processes of streamflow generation during storm runoff, surface water, groundwater, and rainwater samples were collected for environmental isotopes (oxygen-18 and deuterium). Raisin River discharge data were also analysed. Seepage measurements and hydraulic conductivities exhibit significant variability. The coefficients of variation for seepage measurements ranged from 20.3 to 392%, and for hydraulic conductivity from 0 to 161%, depending on the site. Seepage flux ranges from $2.23\times10\sp{-6}$ to $\rm{-}9.82\times10\sp{-9}m\sp3m\sp{-2}s\sp{-1},$ and hydraulic conductivity ranges from 10$\sp{-6}$ to 10$\sp{-9}$ ms$\sp{-1}$ (a negative seepage flux indicates groundwater flow from the aquifer to the river). Environmental isotope analyses indicate that meteoric water is the source of local groundwater with a mean residence time of approximately 4 months. After a storm event, groundwater composed 63% of total stream discharge. The peak response in the river is approximately two days after a storm event. These variables indicate that groundwater/surface water relationships should be taken into account if decisions are made with respect to water quality or quantity. (Abstract shortened by UMI.)

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Madlala, Tebogo Eugene. "Determination of groundwater-surface water interaction, upper Berg River catchment, South Africa." University of the Western Cape, 2015. http://hdl.handle.net/11394/5331.

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>Magister Scientiae - MSc
The present study investigated the application of a multi-method approach to determine groundwater-surface water (GW-SW) interactions to quantify and characterize the quality of water resources in a fractured rock aquifer system in upper catchment of the Berg River (G10A). Demonstrating methods for improved understanding of groundwater and surface water interactions is important for informing development of strategies that ensure effective utilization and management of water resources. Applying a single method to inform innovative strategies for water resources has proved futile. The current study shows how the use of several methods can provide the basis for devising practical strategies for water resource utilization and management. The three methods were applied as follows: First, the base flow separation was used whereby the Chapman and Lynne & Hollick digital filter algorithms were applied to time-series streamflow data from four stream gauging stations in the catchment. The computation from algorithms on three sites (gauging stations) showed that the mean Base Flow Index (BFI) value ranged between 7%-8% for the 2012-2014 periods. This means that discharges from subsurface water storages dominate stream flows throughout the study period. Secondly, the quality of groundwater and surface water was sampled using standard methods. Piper Diagrams generated on Aquachem™ software and radial charts were used to identify the predominant hydrochemical facies. Results showed that Na-Cl was the predominant GW and SW water-type. This means that both GW and SW are mainly influenced by recharging surface water as well as interaction occurring between the rock matrices and infiltrating water. Multivariate statistical analyses were used to evaluate the factors controlling GW and SW chemistry in the upper Berg River catchment and the results showed that GW and SW are influenced by natural processes. Two main factors (a. & b.) were extracted which explained 71.8% of the variation in both GW and SW physicochemical parameters. These factors include water-rock interactions and the recharge of surface water. Cluster Analysis extracted four major clusters that grouped sites with similar physicochemical characteristics together. Finally, differential stream gauging was applied to a 600m reach above the Berg River Dam. Three 200m sub-reaches were used to compute differences in flows between sub-reaches. Stream flow at each sub-reach was estimated using mass balance equations with electrical conductivity measurements during instant salt tracer injection tests. Results indicated that during both the wet season (high flow) dry season (low flow), the river continuously lost water to the subsurface. This was demonstrated by the 0.91m³/s and 2.24m³/s decrease in stream flow along the 600m reach. Dry season flow decreases were less than wet season flow decreases, indicated by markedly lower flow loss in respect to the wet season. This confirms results of the analysis of base flow separation, which indicated that discharges from subsurface storages dominate stream flows during low flow periods. The differential stream gauging approach did not provide distinct points along the selected stream reach where GW-SW interaction occurred; rather it provided a holistic representation of seasonal flow variations along the selected reach. This study showed that upper Berg River catchment is dependent on discharges from subsurface water storages to maintain dry season flows. Furthermore, this study showed that infiltration of surface water and discharge of subsurface water transfers the respective chemical signature of the contributor, meaning that the transfer of water of suitable quality will reduce contamination in the receiving water body (i.e. surface water). Transfer of water between subsurface and surface water contributed an average of 8% of the gauged flows in the catchment between 2012 and 2014, suggesting that the groundwater recharge process dominates this catchment.

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Tanner, Jane Louise. "Understanding and modelling of surface and groundwater interactions." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1012994.

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The connections between surface water and groundwater systems remain poorly understood in many catchments throughout the world and yet they are fundamental to effectively managing water resources. Managing water resources in an integrated manner is not straightforward, particularly if both resources are being utilised, and especially in those regions that suffer problems of data scarcity. This study explores some of the principle issues associated with understanding and practically modelling surface and groundwater interactions. In South Africa, there remains much controversy over the most appropriate type of integrated model to be used and the way forward in terms of the development of the discipline; part of the disagreement stems from the fact that we cannot validate models adequately. This is largely due to traditional forms of model testing having limited power as it is difficult to differentiate between the uncertainties within different model structures, different sets of alternative parameter values and in the input data used to run the model. While model structural uncertainties are important to consider, the uncertainty from input data error together with parameter estimation error are often more significant to the overall residual error, and essential to consider if we want to achieve reliable predictions for water resource decisions. While new philosophies and theories on modelling and results validation have been developed (Beven, 2002; Gupta et al., 2008), in many cases models are not only still being validated and compared using sparse and uncertain datasets, but also expected to produce reliable predictions based on the flawed data. The approach in this study is focused on fundamental understanding of hydrological systems rather than calibration based modelling and promotes the use of all the available 'hard' and 'soft' data together with thoughtful conceptual examination of the processes occurring in an environment to ensure as far as possible that a model is generating sensible results by simulating the correct processes. The first part of the thesis focuses on characterising the 'typical' interaction environments found in South Africa. It was found that many traditional perceptual models are not necessarily applicable to South African conditions, largely due to the relative importance of unsaturated zone processes and the complexity of the dominantly fractured rock environments. The interaction environments were categorised into four main 'types' of environment. These include karst, primary, fractured rock (secondary), and alluvial environments. Processes critical to Integrated Water Resource Management (IWRM) were defined within each interaction type as a guideline to setting a model up to realistically represent the dominant processes in the respective settings. The second part of the thesis addressed the application and evaluation of the modified Pitman model (Hughes, 2004), which allows for surface and groundwater interaction behaviour at the catchment scale to be simulated. The issue is whether, given the different sources of uncertainty in the modelling process, we can differentiate one conceptual flow path from another in trying to refine the understanding and consequently have more faith in model predictions. Seven example catchments were selected from around South Africa to assess whether reliable integrated assessments can be carried out given the existing data. Specific catchment perceptual models were used to identify the critical processes occurring in each setting and the Pitman model was assessed on whether it could represent them (structural uncertainty). The available knowledge of specific environments or catchments was then examined in an attempt to resolve the parameter uncertainty present within each catchment and ensure the subsequent model setup was correctly representing the process understanding as far as possible. The confidence in the quantitative results inevitably varied with the amount and quality of the data available. While the model was deemed to be robust based on the behavioural results obtained in the majority of the case studies, in many cases a quantitative validation of the outputs was just not possible based on the available data. In these cases, the model was judged on its ability to represent the conceptualisation of the processes occurring in the catchments. While the lack of appropriate data means there will always be considerable uncertainty surrounding model validation, it can be argued that improved process understanding in an environment can be used to validate model outcomes to a degree, by assessing whether a model is getting the right results for the right reasons. Many water resource decisions are still made without adequate account being taken of the uncertainties inherent in assessing the response of hydrological systems. Certainly, with all the possible sources of uncertainty in a data scarce country such as South Africa, pure calibration based modelling is unlikely to produce reliable information for water resource managers as it can produce the right results for the wrong reasons. Thus it becomes essential to incorporate conceptual thinking into the modelling process, so that at the very least we are able to conclude that a model generates estimates that are consistent with, and reflect, our understanding (however limited) of the catchment processes. It is fairly clear that achieving the optimum model of a hydrological system may be fraught with difficulty, if not impossible. This makes it very difficult from a practitioner's point of view to decide which model and uncertainty estimation method to use. According to Beven (2009), this may be a transitional problem and in the future it may become clearer as we learn more about how to estimate the uncertainties associated with hydrological systems. Until then, a better understanding of the fundamental and most critical hydrogeological processes should be used to critically test and improve model predictions as far as possible. A major focus of the study was to identify whether the modified Pitman model could provide a practical tool for water resource managers by reliably determining the available water resource. The incorporation of surface and groundwater interaction routines seems to have resulted in a more robust and realistic model of basin hydrology. The overall conclusion is that the model, although simplified, is capable of representing the catchment scale processes that occur under most South African conditions.

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Berger, Karen Plaut 1972. "Surface water-- groundwater interaction : the spatial organization of hydrologic processes over complex terrain." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/80630.

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Mullinger, Neil John. "Radon in groundwater-surface water interactions of lowland Chalk catchments." Thesis, Lancaster University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.524778.

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Meinikmann, Karin. "Groundwater-Surface Water Interactions in a Eutrophic Lake – Impacts of Lacustrine Groundwater Discharge on Water and Nutrient Budgets." Doctoral thesis, Humboldt-Universität zu Berlin, 2017. http://dx.doi.org/10.18452/18203.

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Die Arbeit besteht aus mehreren Studien zur Quantifizierung des Grundwasserstroms in Seen (Exfiltration; engl.: lacustrine groundwater discharge, LGD) und damit verbundener Nährstoffeinträge. In zwei einleitenden Kapiteln dieser Arbeit werden eine Gründe für die Vernachlässigung der Grundwasserexfiltration (LGD) in Seen und der daran gekoppelten Nährstoffeinträge identifiziert. Diese Literaturstudien fassen den aktuellen Kenntnisstand zum Einfluss des Grundwassers auf die Hydrologie von Seen und ihre Nährstoffhaushalte zusammen. Den Kern der vorliegenden Arbeit bilden zwei empirische Studien, die sich mit der Quantifizierung der grundwasserbürtigen Phosphor (P)-Fracht in den Arendsee in Deutschland befassen. Das Gesamtvolumen des Grundwasserzustroms wird basierend auf der Grundwasserneubildung im Einzugsgebiet des Sees ermittelt. Lokale Muster der Grundwasserexfiltration werden anhand von Temperaturtiefenprofilen des Seesediments bestimmt. Eine Kombination der Ergebnisse ermöglicht es, die quantitativen Daten mit lokalen Informationen zu unterstützen. Die Untersuchung der Grundwasserqualität zeigt, dass die P-Konzentrationen im Grundwasser im besiedelten Bereich teilweise stark erhöht sind. Als Konsequenz daraus haben die grundwasserbürtigen P-Frachten einen Anteil von mehr als 50% an der gesamten externen P-Last des Arendsees. Das Grundwasser ist damit eine maßgebliche Ursache für die Eutrophierung des Gewässers. Drei weitere Studien widmen sich der Entwicklung und Optimierung von Ansätzen zur qualitativen und quantitativen Bestimmung der Grundwasserexfiltration in Seen. Die kritische Auseinandersetzung mit den Ergebnissen der Studien zeigt die Notwendigkeit weiterer Forschung zur Verbesserung und Standardisierung der Methoden zur Bestimmung von LGD und damit verbundenen Stofftransporten auf. Der Fall des Arendsees sollte alle, Wissenschaftler und Praktiker, dazu motivieren, das Grundwasser als relevante Eutrophierungsquelle in Betracht zu ziehen.
The present work is a collection of studies on lacustrine groundwater discharge (LGD) and groundwater-borne phosphorus (P) loads. For a number of reasons, groundwater exfiltration (i.e., LGD) is often not considered in water and nutrient budgets of lakes. This is also and especially true for P which was often regarded to be immobile in groundwater until recently. Two chapters review the scientific literature regarding the impacts of groundwater on hydrology and nutrient budgets of lakes, respectively. They present mechanisms and processes of LGD as well as techniques and methods to measure LGD and related nutrient transports. Moreover, numbers of LGD volumes and loads reported in literature are presented. The core of the present work is represented by two case studies dealing with the quantification of P loads from LGD to a lake in Germany. A combination of different methods is applied to overcome the problem of quantitative large scale LGD determination without losing local spatial information. P concentrations in groundwater and LGD are investigated by detailed spatial water sampling. The results reveal that P is actually present in concentrations far above natural background concentrations in the urban groundwater. LGD-derived P loads account for more than 50% of the overall external P loads to the lake and by that contribute significantly to lake eutrophication. Three further studies are devoted to the development and improvement of approaches to determine LGD. Critical reviews of the above mentioned studies reveal the need for further research in order to standardize and improve methods for LGD and mass load determination. It is found that the appropriate method for LGD determination depends on the spatial scale of interest. The identification of P introduced by LGD as a main driver of lake eutrophication is an important finding which should encourage scientists, policy makers, and lake managers to consider groundwater as a relevant P source for lakes.

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Biyela, Mfundi Cyril. "Assessing groundwater-surface water interaction as a decision-making tool licensing water use South Africa : case study area of Gevonden farm." University of the Western Cape, 2015. http://hdl.handle.net/11394/5409.

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>Magister Scientiae - MSc
Assessing groundwater-surface water interaction as a decision-making tool licensing water use South Africa: Case study area of Gevonden Farm is the title of the current study with the context that arises from the use of GRAII methodology which uses quaternary catchment boundaries for groundwater abstraction water use licence application assessment during decision making. The problem is that the quaternary catchment scale approach does not provide the scientific bases for site specific scale. The current study argues that such approach provides realistic, practical information at site specific scale and therefore informs the issuing of licences more accurately. The aim of the current study is to improve understanding of how the assessment of groundwater abstraction water use licence should be carried out at a site specific scale to improve decision making during licence issuance. The objective of the study is to outline the scientific study and demonstrate how the investigation that leads to the decision making can be conducted. The study was carried out using hydraulic methods such as pumping test and geochemical analysis method. Hydraulic properties were determined and chemical elements were analysed for and compared with the SANS 241 water quality standards for domestic and agricultural use. Hydraulic properties such as hydraulic conductivity (K), transmissivity (T), yield and storativity (S) were determined. Major and minor ions that are required to be analysed for domestic and agricultural water use were analysed. Piper diagrams and FC method were used to analyse data. The piper diagrams plotted indicated that surface water is mixing with groundwater and that means there is connection between groundwater and surface water. The chemical elements analysed for were compared with SANS 241 water quality standards for domestic and agricultural use. The water quality on the investigated site can be categorized as having good water quality. A sustainable yield estimated from the two boreholes (BH03 and BH05) which was 1.02 Ɩ/s. The available drawdown estimated with reference to the boreholes water strikes that were determined by EC profiling were 135 mbgl from both boreholes. The study recommends the issuance of water use licence with conditions that chemistry of water should be analysed for once a quarter and boreholes water levels should be analysed for once a month.

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Lovell, Daniel Martin. "Conjunctive management of groundwater and surface water in the Upper Ovens River Valley /." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/5724.

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Pritchard, Jodie Lee, and jodie_pritchard@hotmail com. "Dynamics of stream and groundwater exchange using environmental tracers." Flinders University. School of Chemistry, Physical & Earth Science, 2006. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20060407.122526.

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Regions of surface water and groundwater exchange are major sites for the transfer and transformation of solutes and nutrients between stream and subsurface environments. Conventional stream and groundwater exchange investigations are limited by methodologies that require intensive field investigations and/or the set-up of expensive infrastructure. These difficulties are exacerbated where hydraulic gradients are very low and stream discharge highly variable. This thesis uses a suite of environmental tracers (Cl-, Rn-222, H-2 & O-18, Sr-87/Sr-86) to characterise the extent of stream and groundwater exchange between a sand bed stream and adjacent alluvial aquifer in a subtropical catchment (the Wollombi Brook) of eastern Australia. The aims were to identify sources and relative contributions of different sources of groundwater to stream discharge and specifically to improve the methodology of using Rn-222 to obtain quantitative estimate of groundwater fluxes. The sensitivity of the Rn-222 technique for identifying groundwater discharge based on the Rn-222 concentration in stream water was improved via an iterative numerical approach to account for Rn-222 loss from stream water via turbulent gas exchange and radioactive decay. Optimal distances between stream sampling points for defining the magnitude of groundwater discharge to stream flow based on Rn-222 concentrations in stream water is a function of average stream velocity and water depth. The maximum allowable distance between sampling points for determining the magnitude of groundwater discharge to the Wollombi Brook was 2 km. This work showed that groundwater discharged to all reaches of the Wollombi Brook during baseflow and flood recession conditions. Alluvial groundwater contributed less than 30% of water to stream flow in the mid Wollombi Brook catchment. Dilution of steady-state Rn-222 concentrations measured in transects from the stream to the alluvial sediments showed that significant surface water and groundwater exchange occurs even when gradients between surface water and groundwater are low. Lateral stream water influx to the adjacent alluvial aquifer was more extensive in the lowland areas of the Wollombi Catchment during low flow than flood recession conditions. Extensive stream water influx to the adjacent alluvial aquifer occurs contrary to the net direction of surface water and groundwater flux (as indicated by hydraulic gradients toward the stream channel). The rate of stream and groundwater exchange within the adjacent alluvial aquifer appears to be greatest during baseflow conditions. Fresh alluvial groundwater appeared to provide a buffer against higher salinity regional groundwater discharge to the alluvial aquifer in some reaches of the Wollombi Brook catchment. Pumping of the alluvial aquifer and diversions of surface water may jeopardise the water quality and volume of the alluvial aquifer and induce water flow from the regional aquifer toward the stream, potentially salinising the fresh alluvial aquifer and subsequently the stream. The change in the Cl- concentration and the variation in slope of the deuterium ï¿½ oxygen-18 line between consecutive stream sampling points could be used to differentiate between regional and alluvial groundwater discharge to stream flow. Incorporating this information with three-component end-member mixing using [Sr2+] and Sr-87/Sr-86 showed that stream and alluvial groundwater exchange within the stream channel was highest in the lowland floodplains during low flow conditions. The least stream and alluvial groundwater exchange occurred in the low streambed gradient mid reaches of the Wollombi Brook regardless of stream stage. The greatest difference in the degree of stream and alluvial groundwater exchange between high and low stream stages occurred in the lowland floodplains of the Wollombi Brook.

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17

Meinikmann, Karin [Verfasser]. "Groundwater-Surface Water Interactions in a Eutrophic Lake – Impacts of Lacustrine Groundwater Discharge on Water and Nutrient Budgets / Karin Meinikmann." Berlin : Humboldt-Universität zu Berlin, 2017. http://d-nb.info/1189328070/34.

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18

Ala-aho, P. (Pertti). "Groundwater-surface water interactions in esker aquifers:from field measurements to fully integrated numerical modelling." Doctoral thesis, Oulun yliopisto, 2014. http://urn.fi/urn:isbn:9789526206585.

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Abstract Water resources management calls for methods to simultaneously manage groundwater (GW) and surface water (SW) systems. These have traditionally been considered separate units of the hydrological cycle, which has led to oversimplification of exchange processes at the GW-SW interface. This thesis studied GW hydrology and the previously unrecognised connection of the Rokua esker aquifer with lakes and streams in the area, with the aim of identifying reasons for lake water level variability and eutrophication in the Rokua esker. GW-SW interactions in the aquifer were first studied with field methods. Seepage meter measurements showed substantial spatial variability in GW-lake interaction, whereas transient variability was more modest, although present and related to the surrounding aquifer. Environmental tracers suggested that water exchange occurs in all lakes in the area, but is of varying magnitude in different lakes. Finally, GW-SW interaction was studied in peatland catchments, where drainage channels in the peat soil presumably increased groundwater outflow from the aquifer. Amount and rate of GW recharge were then estimated with a simulation approach developed explicitly to account for the physical characteristics of the Rokua esker aquifer. This produced a spatially and temporally distributed recharge estimate, which was validated by independent field techniques. The results highlighted the impact of canopy characteristics, and thereby forestry management, on GW recharge. The data collected and the new understanding of site hydrology obtained were refined into a fully integrated surface-subsurface flow model of the Rokua aquifer. Simulation results compared favourably to field observations of GW, lake levels and stream discharge. A major finding was of good agreement between simulated and observed GW inflow to lakes in terms of discharge locations and total influx. This thesis demonstrates the importance of using multiple methods to gain a comprehensive understanding of esker aquifer hydrology with interconnected lakes and streams. Importantly, site-specific information on the reasons for water table variability and the trophic status of Rokua lakes, which is causing local concern, is provided. As the main outcome, various field and modelling methods were tested, refined and shown to be suitable for integrated GW and SW resource management in esker aquifers
Tiivistelmä Vesivarojen hallinnassa tarvitaan menetelmiä pohja- ja pintaveden kokonaisvaltaiseen huomioimiseen. Pohja- ja pintavesiä tarkastellaan usein erillisinä osina hydrologista kiertoa, mikä on johtanut niiden välisten virtausprosessien yksinkertaistamiseen. Tässä työssä selvitettiin Rokuan pohjavesiesiintymän hydrologiaa ja hydraulista yhteyttä alueella oleviin järviin ja puroihin. Tutkimuksessa pyrittiin osaltaan selvittämään syitä harjualueen järvien pinnanvaihteluun ja veden laatuongelmiin. Kenttätutkimuksissa todettiin voimakasta alueellista vaihtelua järven ja pohjaveden vuorovaikutuksessa. Pohjaveden suotautumisen ajallinen vaihtelu puolestaan oli vähäisempää, mutta havaittavissa, ja kytköksissä järveä ympäröivän pohjavesipinnan vaihteluihin. Merkkiaineet vesinäytteistä viittasivat vastaavan vuorovaikutuksen olevan läsnä myös muissa alueen järvissä, mutta suotautuvan pohjaveden määrän vaihtelevan järvittäin. Turvemailla tehdyt mittaukset osoittivat pohjaveden purkautuvan ojaverkostoon ja ojituksen mahdollisesti lisäävän ulosvirtaamaa pohjavesiesiintymästä. Pohjaveden muodostumismäärää ja -nopeutta tutkittiin numeerisella mallinnuksella, joka kehitettiin huomioimaan harjualueelle ominaiset fysikaaliset tekijät. Mallinnus tuotti arvion ajallisesti ja alueellisesti vaihtelevasta pohjaveden muodostumisesta, joka varmennettiin kenttämittauksilla. Tuloksissa korostui kasvillisuuden, ja sitä kautta metsähakkuiden, vaikutus pohjaveden muodostumismääriin. Hydrologiasta kerätyn aineiston ja kehittyneen prosessiymmärryksen avulla Rokuan harjualueesta muodostettiin täysin integroitu numeerinen pohjavesi-pintavesi virtausmalli. Mallinnustulokset vastasivat mittauksia pohjaveden ja järvien pinnantasoista sekä purovirtaamista. Työn merkittävin tulos oli, että mallinnetut pohjaveden purkautumiskohdat ja purkautumismäärät alueen järviin vastasivat kenttähavaintoja. Tämä työ havainnollisti, että ymmärtääkseen pohjaveden ja siitä riippuvaisten järvien ja purojen vuorovaikutusta harjualueella on käytettävä monipuolisia tutkimusmenetelmiä. Työ toi lisätietoa Rokuan harjualueen vesiongelmien syihin selittäen järvien vedenpinnan vaihtelua ja vedenlaatua pohjavesihydrologialla. Väitöstyön tärkein anti oli erilaisten kenttä- ja mallinnus-menetelmien soveltaminen, kehittäminen ja hyödylliseksi havaitseminen harjualueiden kokonaisvaltaisessa pinta- ja pohjavesien hallinnassa

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19

Berger, Tobias. "Fluoride in surface water and groundwater in southeast Sweden : sources, controls and risk aspects." Doctoral thesis, Linnéuniversitetet, Institutionen för biologi och miljö (BOM), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-52562.

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The aim of this thesis is to determine the sources, controls and risk aspects of fluoride in surface water and groundwater in a region of southeastern Sweden where the fluorine-rich 1.45 Ga circular Götemar granite (5 km in diameter) crops out in the surrounding 1.8 Ga granites and quartz monzodiorites (TIB rocks). The materials of this thesis include both primary data, collected for the purpose of this thesis, and a large set of secondary data, retrieved from the Swedish Nuclear Fuel and Waste Management Co., the Swedish Geological Survey and the Kalmar County Council. A characteristic feature of the area is high fluoride concentrations in all kinds of natural waters, including surface waters (such as streams) and groundwater in both the Quaternary deposits (regolith groundwater) and bedrock fractures (fracture groundwater). A number of potential sources and controls of the high fluoride concentrations were investigated, including a variety of geological, mineralogical, mineral-chemical and hydrological features and processes. For the stream waters and regolith groundwater, high fluoride concentrations were correlated with the location of the Götemar granite. This finding is explained by the discharge of fluoride-rich groundwater from fractures in the bedrock and/or the release of fluoride due to the weathering of fluorine-bearing minerals in the Quaternary deposits; however, the Quaternary deposits had considerably lower fluoride concentrations than the underlying bedrock. The high fluoride concentrations in the fresh fracture groundwater (up to 7.4 mg/L) in the TIB-rocks are proposed to be the result of long residence times and the alteration/dissolution of fluorine-bearing primary and secondary minerals along the fracture walls. In terms of risk aspects, this thesis shows that fluoride can add to the transport and inorganic complexation of aluminium in humic-rich, acidic streams. Additionally, 24 % of the children in households with private wells in Kalmar County were assessed to be at risk of excess fluoride intake based on the WHO drinking water guideline value (1.5 mg/L). However, the risk increased significantly when instead the US EPA reference dose (0.06 mg/kg-day) was used, both when all relevant exposure pathways were taken into account as well as water consumption alone. Hence, it is shown that the risk of an excess intake of fluoride is strongly dependent on the basis for evaluation.

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20

Sullivan, Pamela L. "Groundwater-Surface Water Interactions on Tree Islands in the Everglades, South Florida." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/474.

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The marked decline in tree island cover across the Everglades over the last century, has been attributed to landscape-scale hydrologic degradation. To preserve and restore Everglades tree islands, a clear understanding of tree island groundwater-surface water interactions is needed, as these interactions strongly influence the chemistry of shallow groundwater and the location and patterns of vegetation in many wetlands. The goal of this work was to define the relationship between groundwater-surface water interactions, plant-water uptake, and the groundwater geochemical condition of tree islands. Groundwater and surface water levels, temperature, and chemistry were monitored on eight constructed and one natural tree island in the Everglades from 2007-2010. Sap flow, diurnal water table fluctuations and stable oxygen isotopes of stem, ground and soil water were used to determine the effect of plant-water uptake on groundwater-surface water interactions. Hydrologic and geochemical modeling was used to further explore the effect of plant-groundwater-surface water interactions on ion concentrations and potential mineral formation. A comparison of groundwater and surface water levels, along with calculated groundwater evapotranspiration rates, revealed that the presence of a water table depression under the islands was concurrent with elevated groundwater uptake by the overlying trees. Groundwater chemistry indicated that the water table depression resulted in the advective movement of regional groundwater into the islands. A chloride budget and oxygen isotopes indicated that the elevated ionic strength of tree island groundwater was a result of transpiration. Geochemical modeling indicated that the elevated ionic strength of the groundwater created conditions conducive to the precipitation of aragonite and calcite, and suggests that trees may alter underlying geologic and hydrologic properties. The interaction of tree island and regional groundwater was mediated by the underlying soil type and aboveground biomass, with greater inputs of regional groundwater found on islands underlain by limestone with high amounts of aboveground biomass. Variations in climate, geologic material and aboveground biomass created complex groundwater-surface water interactions that affected the hydrogeochemical condition of tree islands.

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21

Petersen, Robin Marc. "A conceptual understanding of groundwater recharge processes and surface-water/ groundwater interactions in the Kruger National Park." Thesis, University of the Western Cape, 2012. http://hdl.handle.net/11394/5204.

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>Magister Scientiae - MSc
In the Kruger National Park (KNP) which is the flagship conservation area in South Africa, the impact on groundwater should be kept to a minimum as groundwater plays a vital role in sustaining ecosystem functioning and sustaining baseflow to streams and rivers. For this reason groundwater has been recognized as one of the environmental indicators that need to be monitored. The KNP has adopted a Strategic Adaptive Management (SAM) approach with clear ecosystem management goals. The achievement of these goals is evaluated by using environmental indicators. These indicators are evaluated against thresholds of potential concern (TPC). TPCs are a set of boundaries that together define the spatiotemporal conditions for which the KNP ecosystem is managed. TPCs are essentially upper and lower limits along a continuum of change in selected environmental indicators. Historically, groundwater recharge and surface water interaction with rivers has tended to be overlooked in the KNP. This study proposes a conceptual model of groundwater recharge processes in the KNP, defining when and how groundwater recharge occurs. Two methods were used, the Cumulative Rainfall Departure (CRD) and stable isotopes of ²H and ¹⁸O. An adapted version of the CRD which incorporates a long and short term memory of the system was used to identify possible recharge processes. Further, using the CRD method a reliable reconstruction of the long term groundwater level trends are simulated using monthly rainfall totals with reference to the average rainfall over the entire time series 1936-2009. The stable isotope of ²H and ¹⁸O samples from cumulative rainfall samplers, surfacewater (streams and rivers) and groundwater from boreholes were collected monthly for approximately one year (May 2010 to July 2011). The isotope composition of the groundwater was used to establish whether recharge was immediate or delayed. Additionally, the isotopic composition of surface-water from rivers and streams were compared to that of groundwater to identify surface-water interactions. Groundwater recharge in KNP occurs during the rainy summer months (December to March) and very little to none during the dry winter season (April to September). Recharge takes place during rainfall sequences 100mm or more. The stable isotope records collected from cumulative rainfall, groundwater and surface water (streams and rivers) indicate that groundwater experiences evaporation prior to infiltration. As the KNP experiences high evaporation rates, insignificant rainfall sequences contribute little or zero to recharge. The CRD analysis of groundwater level fluctuations shows that recharge to the aquifers respond to dry and wet cycles that last for 6 to 14 years. The KNP experienced several periods of below-average rainfall and hence no significant recharge took place to the basement aquifers. During a normal rainy season the water levels rise somewhat then starts receding again. It is only during major rainfall events that may occur every 100yrs to 200yrs causing the aquifers to fully recharge. This was perfectly illustrated by the high groundwater levels after the 2000 major rainfall event that recharged the aquifers fully. During below average rainfall years the overall water level trend is drastically declining. The system experiences higher natural losses than gains due to outflow of groundwater to streams and rivers. The KNP is divided down the center by two geological formations, granites along the west and basalts along the east. The combination of the CRD model and the stable isotopic analysis suggest that the dominant recharge processes that occur in the southern region of the KNP are direct recharge via piston flow and indirect recharge via preferred pathways particularly streams and rivers. Along the eastern half of the KNP on the Basalts and Rhyolite direct recharge via piston flow are dominant. Groundwater is not recharged via small streams and rivers (Sweni and Mnondozi Rivers) as it was found that at these particular sites these rivers are detached and do not interact with groundwater. Along the western granitic areas the dominant recharge process are indirect recharge. Recharge takes place via preferred pathways particularly streams and rivers. It was found that ephemeral rivers (Nwatsisonto River) act as sinks for groundwater recharge and influent-effluent conditions are experienced along seasonal rivers (Mbyamiti River). The large perennial Sabie and its tributary the Sand River are consistently fed by groundwater, above all maintaining base flow during the dry season. These rivers act as basin sinks receiving groundwater discharge all year round. Using the stable isotope composition of rainfall, surface-water and groundwater to act as a natural tracer, in combination with the CRD method proved invaluable to confirm the plausible recharge processes. The study provided a conceptual understanding of the groundwater system in the KNP forming the foundation to developing acceptable limits (TPCs) of the groundwater levels in the KNP. The model will serve as a guide for the recharge processes and for deciding on the location and time frames for data collection to ultimately set TPCs for groundwater in the KNP to sustainably manage the resource.

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22

Grant, Jane D. "The significance of groundwater-surface water interactions on hyporheic physico-chemistry and stream ecology in two Scottish mountain rivers." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources. Online version available for University members only until Apr. 7, 2010, 2008. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=26046.

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23

Vionnet, Leticia Beatriz, and Thomas Maddock. "Modeling of Ground-Water Flow and Surface/Ground-Water Interaction for the San Pedro River Basin Part I Mexican Border to Fairbank, Arizona." Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1992. http://hdl.handle.net/10150/614152.

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Many hydrologic basins in the southwest have seen their perennial streamflows turn to ephemeral, their riparian communities disappear or be jeopardized, and their aquifers suffer from severe overdrafts. Under -management of ground -water exploitation and of conjunctive use of surface and ground waters are the main reasons for these events.

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24

Vionnet, Leticia Beatriz, Thomas III Maddock, and David C. Goodrich. "Investigations of stream-aquifer interactions using a coupled surface-water and ground-water flow model." Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1997. http://hdl.handle.net/10150/615700.

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A finite element numerical model is developed for the modeling of coupled surface-water flow and ground-water flow. The mathematical treatment of subsurface flows follows the confined aquifer theory or the classical Dupuit approximation for unconfined aquifers whereas surface-water flows are treated with the kinematic wave approximation for open channel flow. A detailed discussion of the standard approaches to represent the coupling term is provided. In this work, a mathematical expression similar to Ohm's law is used to simulate the interacting term between the two major hydrological components. Contrary to the standard approach, the coupling term is incorporated through a boundary flux integral that arises naturally in the weak form of the governing equations rather than through a source term. It is found that in some cases, a branch cut needs to be introduced along the internal boundary representing the stream in order to define a simply connected domain, which is an essential requirement in the derivation of the weak form of the ground-water flow equation. The fast time scale characteristic of surface-water flows and the slow time scale characteristic of ground-water flows are clearly established, leading to the definition of three dimensionless parameters, namely, a Peclet number that inherits the disparity between both time scales, a flow number that relates the pumping rate and the streamflow, and a Biot number that relates the conductance at the river-aquifer interface to the aquifer conductance. The model, implemented in the Bill Williams River Basin, reproduces the observed streamflow patterns and the ground-water flow patterns. Fairly good results are obtained using multiple time steps in the simulation process.

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25

Valerio, Allison Marie. "Modeling groundwater-surface water interactions in an operational setting by linking RiverWare with MODFLOW." Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1453540.

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26

Vionnet, Leticia Beatriz, and Leticia Beatriz Vionnet. "Investigation of stream-aquifer interactions using a coupled surface water and groundwater flow model." Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187414.

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A finite element numerical model is developed for the modeling of coupled surface-water flow and ground-water flow. The mathematical treatment of subsurface flows follows the confined aquifer theory or the classical Dupuit approximation for unconfined aquifers whereas surface-water flows are treated with the kinematic wave approximation for open channel flow. A detailed discussion of the standard approaches to represent the coupling term is provided. In this work, a mathematical expression similar to Ohm's law is used to simulate the interacting term between the two major hydrological components. Contrary to the standard approach, the coupling term is incorporated through a boundary flux integral that arises naturally in the weak form of the governing equations rather than through a source term. It is found that in some cases, a branch cut needs to be introduced along the internal boundary representing the stream in order to define a simply connected domain, which is an essential requirement in the derivation of the weak form of the ground-water flow equation. The fast time scale characteristic of surface-water flows and the slow time scale characteristic of ground-water flows are clearly established, leading to the definition of three dimensionless parameters, namely, a Peclet number that inherits the disparity between both time scales, a flow number that relates the pumping rate and the streamflow, and a Biot number that relates the conductance at the river-aquifer interface to the aquifer conductance. The model, implemented in the Bill Williams River Basin, reproduces the observed streamflow patterns and the ground-water flow patterns. Fairly good results are obtained using multiple time steps in the simulation process.

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27

Donelan, Jack E. "Groundwater-Surface Water Interaction in the Kern River| Estimates of Baseflow from Dissolved Radon Analysis and Hydrograph Separation Techniques." Thesis, California State University, Long Beach, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10841176.

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Geochemical mixing methods utilizing ²²²Rn and chloride and statistical hydrograph separation techniques were carried out in an attempt to understand baseflow dynamics in a section of the Kern River in the Sierra Nevada of Southern California. ²²²Rn has become a valuable tool for evaluating groundwater inflow to a river, particularly when groundwater and surface water have similar major ion geochemistry. When using geochemical methods it is important to minimize uncertainty through comparison with separate tracers and techniques, though this is complicated in this setting. Snow melt discharge and regulation of natural river flow cause hydrograph-based techniques to suffer from inaccuracies. Geochemical mixing using major ions and stable isotopes are complicated by the chemical similarity between surface water and groundwater. ²²²Rn is a powerful tool to elucidate this relationship in this setting if major uncertainties, like rate of radon degassing and parafluvial and hyporheic radon production can be constrained.

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28

Owor, M. "Groundwater-surface water interactions on deeply weathered surfaces of low relief in the Upper Nile Basin of Uganda." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/19757/.

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Little is known of the interactions between groundwater and surface water on the deeply weathered surfaces of low relief in the Great Lakes Region of Africa (GLRA). The role of groundwater in sustaining water levels in lakes, rivers and wetlands during periods of absent rainfall is also unclear. Indeed, groundwater is commonly excluded from estimations of the surface water balances. Piezometer nests constructed on the shores of Lakes Victoria (Jinja, Entebbe) and Kyoga (Bugondo) through this study, provide the first evidence of the lithologic interface and dynamic interactions between groundwater and surface water in the GLRA. Evidence is drawn from lithological analyses (texture, lithostratigraphy), geophysical surveys (resistivity mapping, VES), hydraulic tests, borehole hydrographs and hydrochemical (major ions, \delta^2H, \delta^1^8O) data. Groundwater interacts with surface waters primarily via preferential pathways within the coarse horizons towards the base of thick saprolite underlying relatively thin (<5 m) fluviallacustrine sands. Hydrological observations and hydrochemical data indicate that groundwater flows primarily into lakes; this interaction is dynamic varying by season and proximity to lake. Interactions between groundwater and Lakes Victoria and Kyoga are also influenced by changing drainage base (lake) levels that are controlled, in part, by regional, rather than local climatology and dam releases from Lake Victoria (Jinja). Groundwater levels are strongly influenced by rainfall-fed recharge that depend more upon heavy rainfall events (10 mm\cdot d^-^1) during the monsoons than the total volume of rainfall; mean vertical velocities in the unsaturated zone are ~1 m\cdot d^-^1. Layered heterogeneity in aquifer properties (hydraulic conductivity, storage) indicate deeply weathered rocks formed under prolonged in situ weathering (etchplanation) of lowrelief surfaces. This layered heterogeneity in the saprolite aquifer gives rise to a twocomponent recession in borehole hydrographs following recharge events. A firstapproximation of the proportion of the Lake Victoria’s water balance supplied by groundwater is derived from new observations in this study and is in the order of 1 %.

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Timani, Bassel. "Innovative and Efficient Simulation-Optimization Tools for Successful Groundwater Management and Conflict Resolution." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4601.

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Decision makers' conflicts about the validity of a single simulation model and inefficiencies of existing response matrix methods (RMM) hinder adopting successful groundwater management plans. We speed up the process by proposing a hybrid RMM that is most efficient for situations in which optimizable stimuli can vary through consecutive periods of uniform duration interspersed with periods of different duration. We use the hybrid RMM within Simulation-Optimization (S-O) models to develop optimal water management strategies. For the tested problems, the hybrid RMM requires as much or 63-89% less computation time than other RMMs. Second, we propose Multi-Conceptual Model Optimization (MCMO) that can help stakeholders reach a compromise strategy instead of agreeing on the validity of a single model. MCMO computes optimal strategies that simultaneously satisfy analogous constraints and bounds in multiple numerical models differing by more than parameter values. Applying MCMO to Cache Valley (Utah, USA) reveals that protecting local ecosystem limits the increased groundwater pumping to satisfy only 40% of projected water demand increase using two models. To successfully and sustainably manage Cache Valley aquifer, we evaluate sustained yield strategies (SYS) and quantify the resilience of a computed SYS. We maximize the number of new residents who can have their indoor and outdoor uses satisfied, subject to constraints on aquifer-surface waters conditions, and limiting new residents to projected increases in population (PIiP). furthermore, we examine the effect of optimization approach and sequiencing, temporally-lagged spatially distributed return flow that is a function of optimal groundwater use, and the acceptability time evaluation on the optimal yield strategy. Cache Valley aquifer can sustainably satisfy the outdoor water demand of 74%-83% and the indoor water demand of 83%-100% of the PIiP. We quantify deterministic resilience Rd(A,T,SV)=P to evaluate how completely an aquifer condition (SV) recovers after the end of climatic anomaly (A), by recovery time (T). Simulation predicts that Cache Valley aquifer system resiliences to a 2-year drought are Rd(2YD, 3 yrs, Overall) = 93% and Rd (2YD,≥8,Overall) ≥ 95%. Proportionally reducing pumping rates by 25% through the time horizon of the simulation increases the overall resilience to 96% within 3 years.

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30

Pöschke, Franziska. "Approaches to identify groundwater discharge towards and within lowland surface water bodies on different scales." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2017. http://dx.doi.org/10.18452/17779.

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Die Arbeit beinhalted verschiedene Studien, die die Grundwasser (GW)-Oberflächenwasser (OW)-Interaktion im Norddeutschen Tiefland untersuchen. Dabei werden zwei Ansätze verfolgt: der hydrogeologische und der limnologische Ansatz. Ersterer betrachtet die Interaktionen aus dem Blickpunkt der unterirdischen Wasserbewegung. Diese ist hauptsächlich gesteuert durch die Verteilung der hydraulische Leitfähigkeit (Sediment) und des hydraulischen Gradienten. Es ist immer noch eine Herausforderung beide Steuerungsgrößen richtig abzuschätzen. Mit neuen Ansätzen, welche auf der Wechselwirkung zwischen verschiedenen Landschafskomponenten basieren (Wasserstände, Topographie, Vegetation, Nährstoffe), wurde klein- bis mesoskalige Sedimentverteilungen in einer Aue untersucht und beschrieben. Des Weiteren konnte mit einem einfachen Grundwassermodell gezeigt werden, das verschiedene Grundwasserstonckwerke (regionale Skala) die Interaktion zwischen GW und einem See beeinflussen können. Der limnologische Ansatz basiert auf der Annahme, dass Bereiche in einem See identifiziert werden können an denen Grundwasser zutritt. In der vorliegenden Arbeit, wurden eine Methode getestet, die auf der unterschiedlichen Temperatur von beiden Wasserkörpern basiert: Im Frühjahr ist das GW wärmer als das Seewasser und sollte sich an der Seeoberfläche einschichten. Mittels thermalen Luftbildaufnahmen sollten somit Grundwasserzutritte identifizierbar sein. Die Studien aber zeigten, dass dies nur unter bestimmten Voraussetzungen möglich ist und seeinterne Prozesse bei der Interpretation der Temperaturverteilung an der Seeoberfläche berücksichtigt werden müssen. Somit besteht noch ein erhöhter Forschungsbedarf bezüglich des limnologischen Ansatzes. Dennoch birgt dieser ein großes Potential, denn er eröffnet die Möglichkeit kurzfristig auf grundwasserbürtige Einträge in OW direkt an der Sediment-Wasser-Grenze zu reagieren und verschafft somit Zeit für aufwändigere hydrogeologische Untersuchungen.
The thesis constists of different studies, which are investigating groundwater-surface water interaction in North-German-Lowlands. Therefore, two different approaches were used: the hydrogeological and the limnological one. The former is based on the classical hydrogeological point of view: the subsurface water movement is mainly driven by hydraulic conductivity (sediment) and the hydraulic gradient. However, the characterisation of both is still a challange. Different methods were used to characterize small- and meso-scale sediment distributions within a lowland floodplain. These are based on the interactions of different landscape components (water level fluctuations, topography, vegetation, nutrient distributions). Furthermore, a simple groundwater model was set up to illustrate how regional groundwater flow impacts local groundwater-lake interactions. The limnological approach is based on the assumption that areas of groundwater exfiltration into a lake are detectable directly at the sediment-water interface. For this purpuse, it was assuemed that temperature differences between both water bodies could be used as follows: in spring the groundwater temperature is higher than that of lakes. Hence, the warmer groundwater float on the lake surface. That should be detectable by thermal infrared imaging. However, the studies could illustrate, that this is only true for specific conditions. Furthermore, lake internal processes need to be considered for interpreting temperature distributions at the lake surface. As a consequence, the limnological approach requires more research activities, since it gives the opportunity to initate short-term measures on groundwater inputs in surface waters. This would also guarantee larger time spans for time-consuming hydrogeological studies.

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Schmidt, Susanne I. "Surface water, groundwater interactions and their association with sediment fauna in a Western Australian catchment /." Marburg : Tectum-Verl, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2660074&prov=M&dok_var=1&dok_ext=htm.

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32

Desilets, Sharon. "Flood Processes in Semi-arid Streams: Sediment Transport, Flood Routing, and Groundwater - Surface Water Interactions." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/195652.

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Flooding in semi-arid streams is highly variable but distinguished from its humid counterpart in terms of forcing conditions, landscape response, flood severity, and stream-aquifer connectivity. These floods have the potential for great benefit in a water-limited environment, but also great devastation when powerful floods encounter human infrastructure. This dissertation employs an integrative approach to address several facets of flooding in semi-arid streams. In particular, information from field sampling during flood events combined with modeling are used to evaluate the processes of post-disturbance sediment transport, flood routing, transient bank storage, and stream disconnection. The major findings show: (1) Suspended sediment composition in floods following wildfire depends on the number, timing, and intensity of preceding storms and flood events, implicating overland flow hillslope processes as a dominant mass wasting mechanism (2) Isotopic chemographs for two representative intense convective storm events demonstrate that the flash flood bore develops from predominantly high elevation event water that overcomes, incorporates, and pushes baseflow to the front of the hydrograph peak (3) Isotope information combined with a plug-flow model can simulate this flood bore mixing process simultaneously in two separate canyons in the basin in order to calculate the timing and quantity of flow; this could be a useful tool for watersheds that are not extensively instrumented, or for calibrating a more complex or distributed model, (4) For a stream connected to an underlying aquifer, a circulation pattern develops at the onset of flooding that causes an upwelling of antecedent water into the unsaturated zone, challenging the assumptions of one dimensional, lateral flow and transport into the streambank, and (5) For small stream-aquifer disconnections, large increases in infiltration, large decreases in seepage, and a dominantly vertical profile for floodwater were observed. This implies that a stream that supports a wide riparian corridor may be in danger of vegetation die-offs with even shallow depletions of the groundwater table.

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Schmadel, Noah M. "Quantifying Surface Water and Groundwater Interactions in a High-Gradient Mountain Stream for Solute Transport." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/486.

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A study reach in a mountain stream highly influenced by groundwater was selected to test common data collection strategies used to characterize and quantify groundwater exchange processes necessary to predict solute transport. The data types collected include: high frequency discharge estimates with the use of rating curves, dilution gauging techniques with instantaneous tracer experiments, groundwater table and stream water surface elevations, vertical head gradients, and hydraulic conductivity estimates. The first two data types were categorized as stream gauging and the remaining three data types as site characterization. The stream gauging data were used to quantify net changes in stream discharge at a reach scale with rating curve predictions and dilution gauging. Each method resulted in opposite net changes at this scale. An error analysis regarding rating curve predictions and dilution gauging suggested that neither method detected groundwater exchange at this scale due to discharge estimates being statistically the same. The error in rating curve predictions was estimated using a 95% joint confidence region of model parameters and the error in dilution gauging was estimated using a first order error analysis. Dilution gauging was also performed at a sub-reach scale to quantify net changes and indicated the groundwater exchange was highly spatially variable, which was not concluded at the reach scale. To quantify a water balance more representative of the exchanges occurring, gross gains and gross losses were quantified by measuring tracer mass recoveries and were found to occur in every sub-reach. However, the error analysis concluded that nearly half of the changes were not significant, which emphasized the importance of quantifying error in stream gauging techniques used to understand surface water-groundwater interactions. The site characterization data were used to test and verify the water balance results by providing information regarding general trends and spatial variability of surface water-groundwater interactions. This study proved that one data type is not adequate to clearly characterize and quantify surface water-groundwater interactions and researchers must exercise caution when interpreting results from different data types at varying spatial scales.

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Hadlock, Gregg L. "Groundwater and Surface-Water Interactions along Lower Medano Creek, Great Sand Dunes National Monument, Colorado." DigitalCommons@USU, 1995. https://digitalcommons.usu.edu/etd/6594.

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The objectives of this investigation are as follows: 1) review the existing hydrogeologic data for the San Luis Valley, the Great Sand Dunes Monument, and Medano Creek; 2) review the surface-water data that have been collected on Medano Creek; 3) collect or review previously collected water-level data obtained in the area of lower Medano Creek and correlate them with the surface-water data; 4) conduct constant-head permeameter tests on sand samples collected near the ground surface along lower Medano Creek; 5) produce a conceptual model of lower Medano Creek; and 6) produce a numerical model of lower Medano Creek that will predict the effect that a lowering of the regional water table could have on the terminus of flow of Medano Creek. The complex hydrogeologic conditions under lower Medano Creek have been approximated with three homogeneous and anisotropic layers. A complex system of confining layers is represented by a single low-hydraulic-conductivity layer in the middle. Numerical-modeling results suggest that the location of the terminus of flow in Medano Creek will recede significantly in response to a lowering of the regional water table, possibly by as much as 21,000 feet (6,400 meters) if the regional water table is lowered 150 feet (46 meters). These results indicate the qualitative effect that a lowering of the regional water table would have on lower Medano Creek, but they cannot be considered to be precise quantitative predictions. The results should be regarded with caution due to the paucity of data available.

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Naugler, Trudy Lynn. "Groundwater - surface water interactions in the Salmon River Watershed, BC : integrating spectroscopy, isotopes, water quality, and land use analyses." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31782.

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Understanding the sources and pathways of water pollutants is critical for protecting freshwater resources. Relationships between water quality and land use can be obscured by variable land use, seasonal variability, and interactions between surface water and groundwater. This research combines the tools of fluorescence spectroscopy, nitrate stable isotopes and water chemistry to better understand land use impacts on water quality. The Hopington aquifer, one of the most vulnerable aquifers in the Lower Fraser Valley, is a source of drinking water for the Township of Langley. This aquifer is also responsible for maintaining the summer stream flow in the Salmon River, a productive Coho salmon stream. Elevated nitrates in both ground and stream water are a concern. Twelve stream sites and eleven groundwater wells were sampled during 2006 to try and "fingerprint" different water sources. Samples were analyzed for: uv-visible absorbance, fluorescence, DOC, nutrients (ammonium, nitrate, ortho-phosphate), chloride, trace elements, and nitrate-isotopes (δ¹⁸0 and δ¹⁵N). The combination of these tools provided a more detailed look at the groundwater - surface water interactions and helped track pollutants within the system. Nitrate concentrations in the Salmon River increase where it cuts through the Hopington aquifer; concentrations peak in August when groundwater makes up the greatest proportion of the stream flow. Humic-like fluorescence was able to measure this groundwater influence because groundwater has much lower fluorescence. Nitrate isotopes showed that inorganic fertilizers were not a dominant source, but that soil N, septic tank leakage, and manure were possible sources. Stream sites influenced by groundwater had an isotopic fingerprint similar to nearby wells, showing that the nitrate source(s) were the same. A GIS-based land use analysis suggested that agricultural land use was having the greatest impact on local water quality, especially on surface waters in the wet season. Protein-like fluorescence showed potential as a tool for pollution monitoring and should be explored further.
Science, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate

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Blumstock, Maria Elisabeth. "Spatial organisation of groundwater-surface water interactions in an upland catchment : integrating hydrometric, tracer and modelling approaches." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=233033.

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This thesis presents studies of the heterogeneous nature of groundwater-surface water (GW-SW) interactions at the hillslope and catchment scale in the 3.2km2 Bruntland Burn, UK. GW fluctuations were measured within three contrasting hydropedological units. Synoptic hydrogeochemical surveys were carried out (major ions, stable isotopes) to capture the increased influence of GW to the stream during a 10year return period drought. The catchment was shown to have highly dynamic GW stores, with each landscape unit translating into different rainfall-runoff processes. Soil characteristics were shown to be the strongest predictors for variability in GW dynamics. Each soil type was characterised by a unique storage-discharge relationship and threshold response with a certain GW level above which lateral flow dominated. On the lower hillslope, predominating lateral flow and little recharge to depth is supported by hydrologically responsive soils. Connectivity between the steeper slopes and the valley bottom, however, needed persistent wet periods to overcome storage thresholds. Here, vertical flow paths recharging deeper GW dominated, with GW levels falling below the soil layer into the underlying drift. It was found that relatively well mixed, near-surface sources of stream flow predominated in wetter conditions, whilst baseflows are variable and reflect a diverse range of GW stores. Geophysics (ERT) and GW level measurements were integrated into MODFLOW-NWT to simulate GW-SW interactions along a representative 2D-hillslope transect. Although only a preliminary model, it was shown that shallow pathways have much shorter residence times, thus maintaining high water tables in the riparian peatlands, than deeper flow paths discharging through the drift and directly into the stream. Largest sources of GW are located within the drift, resulting in complex spatial patterns of runoff generation. This work illustrated the utility of a basic model to predict GW flow paths, highlighting how water and solutes are stored and released in montane headwater catchments.

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Barua, Shovon. "Effect on groundwater quality from proximal surface water bodies and effect on arsenic distribution in Bangladesh: geochemical controls." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/20383.

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Master of Science
Geology
Saugata Datta
The province (upazila) of Matlab in SE Bangladesh is highly affected with elevated concentrations of dissolved As content and widespread fecal contamination in untreated drinking waters. The study area is sedimentologically composed of thick floodplain deposits of Holocene age overlying Plio-Pleistocene grey fine to coarse sands with considerable clays (consisting of Dupi Tila formation). The goal of the current study is to understand the possible impact of co-occurrence of dissolved organic carbon (along with As release) and fecal indicator bacteria (e.g., E.coli) in aquifers from shallow to deep groundwater quality in this area. Nineteen groundwater (spanning a depth range of 14 to 240 m) samples and nine surface water samples (eight ponds and one canal in proximity to the piezometer nests) were collected from four different piezometric nests within north and south Matlab Upazila in Bangladesh during the monsoonal season (Jun-Jul 2014). The analyses of dissolved organic carbon (DOC) and its fluorescence properties indicate that the chemical character of DOC from shallow to intermediate groundwaters (<150 m) and surface water is dominated by more aromatic and humic materials than deeper groundwaters. Both groundwaters and surface waters may receive humic substances leached from soil and/or from the cellular constituents and exudates of indigenous aquatic organisms. Dissolved organic carbons in groundwater and surface waters are composed of predominantly UVA and UVC-humic like along with tryptophan like components. Only 15% of total C is modern carbon at shallowest depths (<30 m) in groundwaters. The recharge source of groundwaters is from local precipitation, with or without some evaporation before infiltration as depicted by the δ2H and δ¹⁸O variations and the water is infiltrating through mostly terrestrially derived weathered sediments into the aquifers. The type of water in the study area is Ca-Na-HCO₃⁻ type. More toxic and soluble As (III) is present in shallow groundwaters (<30 m). High concentrations of As (V) and As[subscript (t)] are observed high in shallow and intermediate depth wells (<150 m). The most probable number based on the Colilert test and qPCR result for E.coli suggest that unprotected surface waters are harbingers for high microbial population compared to hand pumped wells. However, the very low observed concentrations of cultured E. coli (<1-10 MPN/100 mL) and E. coli DNA (<40 Copies/100 mL) in the wells indicates that the abundance of E.coli cells decrease rapidly with residence time in oligotrophic aquifers. Thus, it may be suggested that more humic DOC in shallow and intermediate groundwaters may be involved in complexation or other biogeochemical reactions that may mobilize As in groundwater. The non-indigenous bacteria can be the primary producers of DOC in the aquifers which can be utilizing surface derived DOC.

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38

Abesh, Bidisha Faruque. "Modeling and Understanding Groundwater Contamination Caused by Cyanotoxins from Harmful Algal Blooms in Lake Erie." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1562953927561716.

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39

Banzhaf, Stefan [Verfasser], and Traugott [Akademischer Betreuer] Scheytt. "Interaction of surface water and groundwater in the hyporheic zone – application of pharmaceuticals and temperature as indicators / Stefan Banzhaf. Betreuer: Traugott Scheytt." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2013. http://d-nb.info/1030099650/34.

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40

Malcolm, Iain A. "Groundwater-surface water interactions in the hyporheic zone of salmon spawning streams : hydrology, hydrochemistry and ecological response." Thesis, University of Aberdeen, 2002. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU161207.

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The links between hydrology, hydrochemistry and salmonid ecology were examined in an interdisciplinary study of the effects of hyporheic water quality on the survival and the development of salmonid ova. Three catchments located in the northeast of Scotland were examined. Work focussed on the Newmills Burn, a degraded agricultural catchment. Complementary studies were also undertaken on the Pow Burn, a comparative agricultural catchment, and the Girnock Burn, a contrasting semi-pristine upland catchment. The relative importance of sediment transport, groundwater-surface water (GW-SW) interactions and hydrochemistry, for the survival and development of salmonid ova, was assessed between spawning in autumn, and hatch in spring. Hydrochemical, hydrometric, isotopic and modelling techniques were applied to the problem in an evolving, serial approach to investigation. The infiltration of fine sediment to the streambed was not sufficient to explain observed fine scale spatial variability (<1m), nor complex spatial patterns of sub-surface hydrochemical change. Hydrochemical and piezometric data indicated that the observed spatial and temporal patterns could be explained by variable contributions of chemically reduced groundwater to the hyporheic zone. At the catchment scale, gross differences in land-use and channel characteristics substantially affected GW-SW interactions and consequently in-redd water quality. At the reach scale, local GW-SW interactions were controlled by geomorphology and riparian sedimentary stratigraphy. At the scale of individual redds, the influence of groundwater generally increased with depth into the hyporheic zone. Dissolved oxygen (DO) levels were implicated as the dominant control on in-redd mortality. Embryo survival and development correlated with mean DO concentrations. Mortality rates from samplers located within artificial redds ranged from 0-100% and showed a significant inverse relationship with mean DO concentrations (r2 = 0.85, P < 0.01). Where embryos survived, low DO affected rates of development. Embryos exposed to low DO concentrations retained a higher portion of the yolk sac mass near to hatch than those developing in more favourable conditions.

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41

Greenberg, Marc Samuel. "Defining Benthic Organism Exposure: Bioavailability and Effects of Non-Polar Organics." Wright State University / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=wright1074096654.

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42

Fleming, Brandon J. "Effects of anthropogenic stage fluctuations on surface water/ground water interactions along the Deerfield River, Massachusetts." Amherst, Mass. : University of Massachusetts Amherst, 2009. http://scholarworks.umass.edu/theses/226/.

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43

Amey, Katherine Springer. "Hydrology And Predictive Model Of Headwater Streams And The Groundwater/Surface Water Interactions Supporting Brook Trout Habitat In Northeast Ohio." Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1301618586.

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44

Wickham, Matthew Prior 1959. "The geochemistry of surface water and groundwater interactions for selected Black Mesa drainages, Little Colorado River basin, Arizona." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/192063.

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Surface water and groundwater interactions involve complex physical processes that are not easily measured in most natural systems. Many of these processes can be indirectly evaluated by examining the geochemistry of the hydrologic system. In this investigation, a geochemical approach to investigating surface water and groundwater interactions is applied to perennial reaches of selected Black Mesa drainages in northeastern Arizona. The drainages, Moenkopi Wash and Dinnebito Wash, receive groundwater discharging from the regional Naquifer. Groundwater within the confined portion of the N-aquifer is chemically and isotopically distinct from that in the unconfined portion. Water in the majority of the confined N-aquifer exhibits a depleted δD and δ¹⁸O composition, a consequence of recharge under an earlier paleo climate. The small changes observed in chemical composition of baseflow along the streamcourse can be explained by chemical interaction with channel alluvium or minor exchange with groundwater from the alluvium.

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45

Howden, Nicholas John Kenneth. "Hydrogeological controls on surface/groundwater interactions in a lowland permeable chalk catchment : implications for water quality and numerical modelling." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431082.

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46

Holmes, Stuart W. "Investigation of Spatial and Temporal Groundwater Thermal Anomalies at Zanesville Municipal Well Field, Ohio: Implications for Determination of River-Aquifer Connectivity Using Temperature Data." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1462026430.

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47

Smith, Donna Lee. ""Redox pumping" in the near surface Missoula aquifer iin the flood plain of the Clark Fork River surface, water and groundwater interaction and arsenic related chemistry at a compost facility near a wastewater treatment plant /." CONNECT TO THIS TITLE ONLINE, 2008. http://etd.lib.umt.edu/theses/available/etd-06062008-105818/.

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48

McGrath, Elinor Olivia. "Salmonid distribution in relation to stream temperatures in Fortune Creek, British Columbia : the influence of surface water and groundwater interactions." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/24182.

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There is concern over the impacts of increased water temperature on salmonid populations in British Columbia’s (BC) Southern Interior. Groundwater influx may moderate stream temperatures and provides thermal refuge for salmonids. The objective of this study was to establish quantitative linkages among groundwater, water temperatures and juvenile coho salmon (Oncorhynchus kisutch Walbaum), Chinook salmon (Oncorhynchus tshawytscha Walbaum) and rainbow trout (Oncorhynchus mykiss Walbaum) in Fortune Creek, a small regulated stream in BC’s Southern Interior. In addition, this study quantified whether groundwater influx could provide thermal relief to salmonids during periods of heat stress. Salmonid enumeration and field data collection were carried out between July 2008 and June 2009. Generalized Linear Mixed Models (Poisson and logistic regression) were used to establish linkages between juvenile salmonids and physical and chemical fish habitat indicators. Thermal modeling of vertical groundwater fluxes in the streambed was conducted using the software VS2DH, which simulates fluid and conductive-convective heat transport. The relative influence of groundwater and stream discharge on stream temperatures was assessed using a conceptual energy balance approach. Statistical modeling confirmed that the distribution of juvenile salmonids was consistently related to water temperatures. Salmonids avoided reaches where maximum daily water temperatures exceeded 22°C, which was exceeded at most of the sites studied. Relationships to water chemistry were less consistent and existed almost exclusively in combination with water temperature variables. While groundwater flux to the stream was widespread, estimated upward fluxes were low (10-7 m/s) and were primarily constrained by low streambed hydraulic conductivities. The influence of advective cooling on stream temperatures in unshaded reaches was too small to provide significant thermal relief for salmonids. However, groundwater influx provided up to 88% of baseflows during the summer low flow season and was critical in maintaining flows in the creek. Conceptual energy balance modeling confirmed that low flows in Fortune Creek limit juvenile salmonid rearing by causing water temperatures to escalate. Recommendations for maintaining suitable water temperatures for juvenile salmonids include re-vegetation of the banks to provide shade and strategically supplementing flows to increase discharge at times of high water temperature potential.

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Hatch, Christine E. "Spatial and temporal dynamics of surface water-groundwater interactions using time-series analysis of streambed thermal records in coastal streams /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2007. http://uclibs.org/PID/11984.

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Maier, Nadine [Verfasser]. "A new method for spatio-temporally explicit predictions of groundwater, surface water and habitat interactions in riparian ecosystems / Nadine Maier." Gießen : Universitätsbibliothek, 2018. http://d-nb.info/1168145619/34.

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Dissertations / Theses on the topic 'Surface water and groundwater interaction'

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